Drive for roll crushers



Nov. 18, 1969 H. HANSEN DRIVE FOR ROLL CRUSHERS Filed Aug. 27, 1965 FIG INVENTOR.

HANS I. HANSEN BY g FIG 2 ATTORNEY United States Patent 3,478,972 DRIVE FOR ROLL CRUSHERS Hans I. Hansen, Cedar Rapids, Iowa, assignor to Iowa Manufacturing Company of Cedar Rapids, Iowa Filed Aug. 27, 1965, Ser. No. 483,037 Int. Cl. B02c 1/08, 15/00, 4/00 U.S. Cl. 241230 5 Claims ABSTRACT OF THE DISCLOSURE A roll type crusher in which the drive roll incorporates a hydraulic pump driven thereby and the driven roll a hydraulic motor driven by the pump. Finger gears and other similar forms of interconnection between the rolls for driving one from the other are thereby eliminated, adjustment of roll spacing is more readily accommodated, and wear greatly reduced.

BACKGROUND OF THE INVENTION As is well known, crushers of many different types are used to reduce the size of material such as rock or stone to a smaller size aggregate for use as base material for hard surface roadways, as aggregate for use in the manufacture of concrete, as top surfacing material for roads, etc. One of the commonly used types of crushing apparatus is the roll crusher which is generally employed as the secondary crushing unit fed in turn by a jaw-type primary crushing unit. As is well known to those skilled in the art, the roll crusher has two rolls rotating about substantially parallel axes whose outer surfaces are spaced apart a predetermined distance. These rolls are driven in opposite directions, and the material to be crushed is gravitationally fed between the rolls, the finer crushed aggregate being discharged onto a screen or conveyor for further handling or processing.

It is essential to efficient operation of the unit that the two crusher rolls each rotate at substantially the same speed at all times, even if temporary misalignment is caused by a surge of material or by the passage of tramp iron. On some types of roll crushers, the rolls are driven and coordinated by a sprocket and chain arrangement. However, on larger models the so-called drive roll is driven either directly from a power source or through speed reduction means and finger gears are used to transmit power to the driven roll from the drive roll. The finger gears permit operation of the crusher rolls at substantially the same speed, regardless of the spacing between the rolls owing to passage of foreign material therethrough, and assure smoothness of operation of the rolls at all times. comparatively little power is required to drive the driven roll from the drive roll because of the interaction of the rolls during the crushing operation and because the load on the rolls is small when material is not being fed to them. However, the finger gears are relatively expensive, must be constantly lubricated, and are subject to wear.

SUMMARY OF THE INVENTION The chief object of the invention is to provide an improved drive for roll crushers of the type described. To this end, the drive roll, which is itself driven from a power source in conventional manner, has a hydraulic pump fitted to and driven by its shaft. The driven roll, in turn, has a hydraulic motor fitted to and driving the corresponding end of its shaft. The hydraulic pump and motor are interconnected by flexible hoses of sufiicient length to accommodate adjustments in the spacing between the rolls. Preferably, the pump, motor and their interconnecting hoses form a closed hydraulic system supplied from a suitable reservoir. Since comparatively little power is needed, the hydraulic components may be rela- 3,478,972 Patented Nov. 18, 1969 tively compact and by their nature are silent, wear little and yet provide efficient coupling between the rolls, whereby the latter are driven at equal and uniform speeds.

FIG. 1 is a side elevational view showing the major components of a roll crusher of the type to which the invention relates; certain portions of the drive mechanism being broken away to illustrate more clearly the crusher rolls; and

FIG. 2 is a top view of the roll crusher of FIG. 1 with portions of the drive unit shown in section to reveal details of the drive mechanism.

The crushing unit as shown in the drawings is supported by a rigid frame 10 which includes longitudinal supporting I-beams 11. Mounted upon the frame 10 is the drive roll 12 which is fixed to a shaft 14 journaled in suitable bearings 16 affixed to the frame 10 on top of the beams 11. A shaft 18 is affixed to the driven roll 20, equal in diameter to drive roll 12, and is journaled in suitable bearings 22 which are seated in housings 24 horizontally slidably mounted on top of the beams 11. The shaft 18 for the driven roll 20 is located parallel to the shaft 14 of the drive roll 12, the shafts being spaced apart a sufficient distance to provide the desired spacing between the outer surfaces of the rolls. The housings 24 are of a construction well known to those skilled in the art in order to provide for adjustment of the crushing setting or distance between the rolls. The housings 24 thus may, for example, employ compressed coil springs 26 thereagainst which maintain the proper amount of force on the driven roll 20, yet provide sufficient resiliency to relieve undue stress and prevent breakage of components in the event of overloads between the rolls, such as may occur during the passage of tramp iron therebetween. Suitable shims 28 or other adjustable means are provided to permit the spacing of the rolls to be varied thereby providing for adjustment of the crusher setting. Alternately, gas hydraulic springs of the nature shown in U.S. Patent 3,315,902 to Pollitz may be employed for the same purpose.

The drive unit of the illustrated embodiment includes a combination flywheel and drive pulley 30 that is rotatably driven from a suitable power source (not shown). The drive pulley 30 is mounted on one end of and drives a countershaft 32 that is journaled in suitable bearings 33 which are preferably enclosed within a tubular housing 34. This construction protects the bearings and shaft from dust and rock and also serves as a lubricant reservoir for the two bearings 33. As shown, the countershaft 32 is located parallel to the roll shafts 14 and 18, and is mounted at one end of the frame 10 near the drive roll 12. At the end of countershaft 32 opposite the drive pulley 30 there is afiixed a pinion gear 36 which serves to transmit power from countershaft 32 to a spur gear 38 on the extended end of drive roll shaft 14. The pinion gear 36 and spur gear 38 are preferably enclosed within a fluid-tight housing 40 which contains suitable lubricant for the gears.

The drive roll 12 is thus directly driven through a gear arrangement which provides the desired speed reduction. While the driven roll 20 is not directly driven by the countershaft 32, yet is must have the same peripheral speed as the drive roll 12 regardless of the rate of feed to the rolls and regardless of any temporary misalignment of the rolls caused by the passage of tramp iron or other uncrushable material. For this purpose the other end of drive roll shaft 14 is provided with a hydraulic pump 42 of any suitable type and design. The pump 42 is driven as roll 12 rotates and is used to drive a hydraulic motor 44 that is mounted on the corresponding end of the driven roll shaft 18. Suitable hydraulic pumps and motors are manufactured, for example, by the Energy Manufacturing 6 Company of Monticello, Iowa. The pump 42 and motor 44 are inter-connected by suitable hydraulic lines 46 and 48 having generous loops therein to accommodate alteration of the spacing between the rolls. In addition, a fluid reservoir and a relief valve (not shown) are also suitably connected into lines 46 and 48, thus forming a closed, self-contained hydraulic system which of course includes a suitable non-compressible hydraulic fluid. If desired, a hopper .50 or other suitable means can be provided to guide the material to be crushed into the space between the rolls 12 and Because of the interaction of the rolls during crushing, a relatively small amount of power is required to drive the driven roll 20 from the drive roll 12. Of course, when no material is being fed to the roll, the load on the rolls is small and, again, little power is required to drive the driven roll even though there is no interaction between the rolls. The hydraulic pump 42 and motor 44 therefore provide a very satisafctory drive which is less cumbersome than that using finger gears and will provide for equal speed of the rolls and smooth operation regardless of temporary misalignment of the rolls or regardless of the crushing setting. In addition, obviously far greater variations in spacing between the rolls can be accommodated than in the case of finger gears. The latter also inherently require considerable backlash, in order to be operative, which backlash, of course, is wholly eliminated in the case of the hydraulic drive. There is little or no wear of the hydraulic components, in contrast to finger gears, so that they have extremely long life and require little or no maintenance. In addition, the hydraulic components are extremely compact and so save space, as well as being relatively light in weight. The hydraulic drive arrangement therefore provides an extremely simple, inexpensive, and satisfactory means for the drive on roll crushers of the type illustrated herein.

Having thus described the invention, it will be obvious to those skilled in the art that various revisions and modifications can be made therein without departing from the spirit and scope of the invention. Thus all such revisions and modifications are intended to be included Within the scope of the following claims:

I claim:

1. In roll-type crushing apparatus having a drive roll rotatable about a fixed axis and a driven roll rotatable abount an axis parallel to said fixed axis, said rolls being rotated in opposite directions with their outer surfaces spaced apart a predetermined distance effective to reduce the size of material gravitatingly fed therebetween, said driven roll being mounted to permit adjustment of the spacing between said roll surfaces and to absorb overloads therebetween by resiliently increasing said spacing, and drive means for rotating said drive roll in one of said directions, the combination therewith of a hydraulic pump operatively connected to and driven by said drive roll, and a hydraulic motor hydraulically connected to and driven by said pump, said motor being operatively connected to said driven roll effective to drive the latter in the other of said directions at substantially the same peripheral speed as that of said dive roll.

2. A roll-type crushing apparatus for reducing the size of crushable material, said apparatus comprising a supporting frame, a drive roll journaled on said frame for rotation about a fixed axis, a driven roll journaled on said frame for rotation about an axis parallel to said fixed axis, said rolls being rotated in opposite directions with the outer surface of the driven roll being spaced a predetermined distance from the outer surface of said drive roll effective to crush said material gravitatingly fed therebetween, means for adjusting said predetermined spacing, means resiliently mounting said driven roll to accommodate movement thereof away from said drive roll upon the passage between said rolls of uncrushable material and to provide for return of said driven roll to its original position after passage of said uncrushable material, a mechanical drive unit for said drive roll adapted for mechanical connection to a power source in order to provide rotation of said drive roll at a desired peripheral speed in one of said directions, a hydraulic pump mounted to and mechanically driven by one end of said drive roll, and a hydraulic motor mounted to and mechanically driving one end of said driven roll for rotation thereof in the other of said directions, said hydraulic pump and motor being hydraulically interconnected and effective to rotate said driven roll at substantially the same peripehral speed as that of said drive roll.

3. The device of claim 2 wherein said hydraulic interconnection comprises a pair of flexible conduit members for passage of hydraulic fluid between said pump and motor, said conduit members having lengths suflicient to accommodate said alterations in the spacing between said rolls.

4. Roll-type crushing apparatus comprising a drive roll rotated in one direction about a fixed axis, a driven roll rotated in the opposite direction about an axis spaced from said fixed axis, said directions of rotation and said spacing being effective to reduce the size of crushable material fed between the peripheral surfaces of said rolls, said driven roll being resiliently movable relative to said drive roll generally toward and away from said drive roll to provide for the passage of uncrushable material between said rolls, mechanical power means for positively rotating said drive roll at a desired peripheral speed in said one direction, and hydraulic power transmission means operatively associated with and hydraulically interconnecting each of said rolls for rotating said driven roll in said opposite direction at substantially the same peripheral speed as that of said drive roll, said hydraulic power transmission means being mechanically connected to each of said rolls and driving said driven roll by virtue of said hydraulic interconnection.

5. The device of claim 4 wherein said hydraulic power transmission means comprises a closed, self-contained hydraulic system including a hydraulic pump, a hydraulic motor and a pair of conduits interconnecting said pump and motor effective to permit said pump to drive said motor even during said resilient movement of said driven roll with respect to said drive roll, and a non-compressible fluid within said system.

References Cited UNITED STATES PATENTS 2,581,010 1/1952 Findley -52 2,935,388 5/1960 Hartmann 241-230 X 3,099,406 7/1963 Kautz 241-231 X 3,307,490 3/1967 Noren 60-52 1,130,365 3/1915 Altheide 241-227 1,450,901 4/ 1923 Kollberg.

1,761,268 6/1930 Maclennan 241-231 1,980,882 11/1934 See 241-231 X 2,143,498 1/ 1939 Reichert 241-231 3,315,902 4/ 1967 Pollitz 241-231 ROBERT C. RIORDON, Primary Examiner D. G. KELLY, Assistant Examiner 

